Hydraulic jack



L. C. STU KEN BORG April 12, 1932.

HYDRAULIC JACK 1930 3 sheets-Sheet 1 Filed Nov. l2,

April 12, 1932. STUKENBORG 1,853,095

HYDRAULIC JACK Filed Nov. l2, .1930 3 Sheets-Sheet 2 April `12, 1932. L. c. STUKENBORG 1,853,095

HYDRAULIC JACK Filed Nov. l2, 1930 3 Sheets-Sheet 3 Patented Apr. 12, 1932 UNIT-En STATES PATENT oFFicE LOUIS G. STUKENLBORG, OF MEMPHIS, TENESSEE HYDRAULIC JACK Application led November 12, 1930. Serial No. 495,068.

This invention relates to lifting jacks, in which the raise of the plunger is accomy plished through the medium of a liquid, or-l dinarily oil, and especially to lifting jacks used for raising automobiles for the purpose of servicing them, in which the jack comprises an elongated cylinder which is disposed in a hole dug in the ground whereby the cylinder is not readily accessible after it has been put in place, and which j ack-employs a correspondingly elongated piston or plunger and heavy super-structure carried by the plunger, which latter unit by reason of its size, shape and weight, is extremely diicult to remove from' the cylinder.

It further relates to a device of this char.

' A In jacks of the type referred to the plunger employed is hollow and Vforms a reservoir for the oil used for lifting purposes. It also forms a casing which encloses aswell as carries the pump and motor by which the oil is transferred from the plunger to the cylinder to accomplish raising of the plunger.

The primary object of the present invention is:

To make a self-contained removable unit of the pump, motor, and release mechanism which may be inserted and secured within the plunger as a unit, and, as a unit be removed therefrom' for servicing and repair.

A further object is to provide means for connecting and disconnecting the pump from the plunger whereby delivery of the oil from the pump to the exterior of the cylinder is accomplished, which connecting means will permit the' ready removal from, and replacement of the pump unit within, the plunger.

The means by which the foregoing and other objects are accomplished and the manner of their accomplishment .will readily be understood from the following specification on reference to the accompanying drawings, in which:

Fig. 1 is a sectional elevation taken on the vertical center line of the plunger and cylinder showing the preferred form of my dev1ce.

Fig. 2 is an enlarged sectional elevation showing a detail of the means by which the 'connection is made between the pump discharge and the discharge pipe leading therefrom to the, outside of the plunger.

Fig. 3 is a section identical to Fig.. 1, ex-

cept that it shows a modied form of the connection between the pump and the discharge ipe. P Fig. 4 is an enlarged fragmentary sectional elevation kshowing the detail of the means employed in making this connection.

Fig. 5 is an additional sectional elevation on the center line of the plunger and cylinder showing an additional modification of vthe means for connecting the pump and the discharge opening between the plunger and cylinder.

Referring now to the drawings in which the various parts are indicated by numerals, 5

10 is a Vertical cylinder having a closed bottom end 11 which cylinder is disposed with its upper end at the surface of the ground, and substantially the ent-ire ,cylinder below the ground. 12 is an annular plunger guide and 13 a stuffing box and packing at the upper end of the cylinder. Disposed within this cylinder is a plunger 14 comprising a hollow cylinder, closed at its lower end by a head lwhich is preferably welded in place. Integral with the upper end of the plunger is an annular flange 16 to which is secured a head 17 as by bolts 18, and which head carries rails 19 'such as are now commonly used in vehicle lifts, and which are usually designated as a table. This table ymay be of any desired type such as the free-wheel type, be-

ing that shown, or the wheel-supporting type,

or of any other desired conformation, the detail of the head and table not being apart of the present invention.

The upper end of the plunger is closed by a roo removable plate 20, preferablyheld'in place by cap screws 21. Secured to and supported by this plate is an electric motor 22 the wiring and source of power not being shown since it is .of usual type. The motor maybe integral with the plate or it may be secured 4thereto as by bolts or cap screws 23. Depending from the motor are posts 24 to which. a pump 25 is secured as by the bolts or cap screws 26. 27 is the motor shaft, 28 the pump shaft and 29 a coupling securing them to ether.

The pum is provided wit a suction inlet 30 from whlch a dependin pipe 31 is carried v which surrounds the pipe 37.

A'box 39 is internally threadedad'acent its downward within and su stantially to the bottom of the plunger. Preferably the lower end of this pipe is provided with a screen 32. The pump also has a discharge outlet 33 which has been brought to central position, beneath and in axial alignment with the pump and motor shaft. 34 is a short nipple secured in this opening and 35 a check va ve secured on this nipple. Disposed below and carried by this check valve, is a T- 36 from,

lower end and is preferably provi ed below such threaded ortion with a. flared skirt 41. of the discha pipe 38 is The lper en vprovi e with a' thread, com ementary to the stuilin box thread, where y the stufiing box may screwed down thereon to compact the acking 40 and make a sealed joint between t e pipes A 37A and 38.

Secured to and depending from the pump 25 are arms42 which extend downward outside of the stuing box 39 and which arms engageI forked lugs 43 which are integral with the stufling box. In order that there may be no possibility of displacing the stuing box with reference to these arms, pins 44, preferabl cotters, are passed through the lower ends o these arms.

j Leading laterally from the T 36/is a nipple 45 on which is mounted a release valve 46 from which a control rod 47 leads upward through the plate 20. The detail of the release valve and the o erating mechanism for the control rod not being a part of the present invention are not here shown.

The pump, motor, check valve, and release valve constitute the parts of this device which under ordinary. circumstances need repair.

In the description just set out and in the following descriptions they constitute a unit which may be readily removed to accomplish such repair.

engaged overthe pipe 38 andI Ordinarily the plunger with this unit in place is shipped from the factory ready for installation. Thereafter in case repairs are necessary or if for other reasons, it is desired toremove the unit the cap screws 21 are removed freeing the plate 20. This plate may then be turned, thereby turning all the parts of the unit and the gland 39 be unscrewed from the pipe 38 after which the entire unit may be lifted out of the plunger and become accessible for such purposes as may be desired.

After repairs have been made the unit may be replaced in the plunger. As the unit is lowered the skirt 41 is easily en aged over the end of the pipe 38 thus centering the device and guiding the pump and plunger discharge pipes into alignment, and the gland may then be screwed tight com acting the packin 40 and sealing the joint between the pipes 3 and 38.

It will be noted that provision is also made by such a joint for yinequalities of pipe len lhs since the packing 40 and its surroun inggland may occupy any ortion of the length of the pi e 37. It will o course be understood that the detail of the joint between these ipes is illustrative only and is intended mere y to typify a packing joint tightened in the manner shown.

In Figs. 3 and 4, I have shown a modified form of the device in which a pipe 37A extends downward from the T 36 this pipe being provided with a ange 50 which forms an abutment for packing 51. If desired, an additional fiange 52 may be emplo edt su port the packing on the pipe. he outsi e diameter of the flanges 50 and 52 is less than the inside diameter of the discharge pipe 38A'4 which is used in this case: 53 is a ared skirt l.

on the upper end of the pipe 38A. In Fig. 4,

, the pipe 38A is shown as the packin is beginning to seat against the inner wal of the pipe 38A. The joint in this case is made byV forcing the pipe 37A downward thus compressing the packing 51 between the outside of the'pipe 37A and the inside of the pipe 38A. It will be noted in this case also that compensation is provided for variations 'in pipe length. In this form of the device the cap screws 21 which hold the 4plate 20 down serve also to hold the joint durlng use. In remov ing this -form of device the cap screws' are ,loosened and-the unit as before described, is raised thus withdrawing the packing and freeing the joint. In replacing the unit the lower end o the pipe 37A is engaged in and guided by the skirt 53 so that installation is easily accomplished, and the completion of the installation is accomplished by screwing.

down the cap screws 21 which hold the plate 20 in place.

In ,the iirst described form it is essential that the pipes 37 and 38 be centrally disposed in the plunger in the form thus described, this lao is also preferablein this case but not essential. In Fig. 5,1 show a further modification in which a flexible pipe 60 is used instead of the discharge pipe 38 or 38A as the case may be. This discharge pipe is connected by a -union 61 to a nipple 62 which leads from the "l" 36 between the check valve 34 and the release valve 46. The length of the pipe G0 is made sufficient to permit the entire unit to be raised until the union is above the top of the plunger and is thereby made accessible so that it may be connected or disconnected. In removing the unit when using'this form of device the cap screws are loosened, the unit is raised untilthe union is in the clear and the pipe 60 then discnnected. In replacing the device the union is 'iirst connected and tightened and the unit thereafter lowered into the plunger and secured as before. It will be noted in this type of device that it is immaterial whether the discharge opening on the pump is in the bottom or at the side thereof.

Itwill be noted in all of the forms shown that the pipe connection is extensible, to a greater or less extent, and that accomplishment of the coupling is made possible by detaehment of the jack-actuating unit from the plunger.

I-Iaving described my invention, what I #claim is,

l. In a hydraulic jack, an elongated hollow plunger closed at its lower end and forming a reservoir for the lifting liquid, said end having a centrally disposed discharge opening therethrough, a lift-actuating unit adapted to be disposed within and carried by the upper end of said plunger, said unit includinga pump, and rendering the lower end of said plunger inaccessible; and means for connecting said plunger opening andthe pump discharge comprising a pipe extending longitudinally upward from said opening along' the center line of said plunger, a pipe extending downward from said pump, one of said pipes telescoping within the other thereof, a coupling part snnilarly slidable along said rst pipe, complementary coupling means on the other of said pipes, and means carried by and actuata-ble through said lift unitfor accomplishing connectionand tightening of said couplingparts.

2. In a hydraulic j ack, an elongated hollow plunger closed at its lower end and forming a reservoir for the lifting liquid, said end having a discharge opening therethrough, a lift-actuating unit adapted to be dis osed within and carried by the upper end o said plunger, said unit including a pump, and means for connecting said plunger opening and the pump discharge comprising a pipe extending upward from saidopening, a pipe extending downward from said pump, one of said pipes telescoping within the other thereof, packing carried by one of said pipes, and coacting with the other thereof, and

means carried by and actuatable throughA said lift unit for accomplishing compression of said packing to seal said pipes together.

3. In a hydraulic jack, an elongated hollow plunger closed at its lower end and forming a reservoir for the lifting liquid, said endv having a discharge opening therethrough, a lift-actuating unit adapted to jbe disposed within and carried by the upper end of said plunger, said unit including a pump, normally inaccessible means for connectin said plunger opening and the pump disc arge comprising complementary separable coupling parts, connections, one from said pump to one part of said coupling and one from said opening to the other part of said coupling, means for guiding said coupling parts into alignment, and means actuatable through said unit slidably-'engagingone of said coupling parts for actuating it to accomplsh connection of said arts.

In testimony whereof hereunto aix my signature.

LOUIS C. STUKENBORG. 

